Text only version

Making it in a Tough Environment


Lots of things in our homes and schools and workplaces -- and in wild and natural places -- can cause harm sometimes. Why "sometimes"? The harm may depend on who you are as well as what you do, what you are exposed to, and when.

Big people have health problems too!Big, muscular people look as if they can resist anything. But they can have allergies or asthma, or be injured by chemicals, too. And the bigger they come, the more skin the sun can burn!

Most of us, for example, can get sunburned on a bright day. Your reaction will be greater if you are outside, without much on, for a long time. Your reaction will be less if you cover your exposed skin with lots of sun screen. How badly you burn can depend on your age and previous exposure. (Babies and toddlers need a lot more protection.) Finally, if one or both of your parents burn very easily, they may have passed that sensitivity to you in your genes.
For more information about sun safety, download the Sunwise Activity BookLink to a Non-NIEHS Site, the Sunwise StorybookLink to a Non-NIEHS Site, and all the other Sunwise School publicationsLink to a Non-NIEHS Site created by the Environmental Protection AgencyLink to a Non-NIEHS Site to promote sun-safe behavior at any age.



Designer Genes -- They're the Boss!



Genes are the instructions -- the marching orders -- that direct our growth, what we look like, and how we react to things in our world, or environment.

Each human - whether infant, child, teen or adult - has 70,000 pairs of these orders, or genes. They tell our bodies' cells what to be and how to behave.

Do you remember transformer toys? You twisted them one way and they were space ships. You twisted them another way and they became robot warriors. Well, under the genes' orders, the cells become the ultimate in transformer robots. The genes instruct our original dab of cells, as they divide, to become different - muscle, bone, lung, or brain cells, or part of a toe. As a result of what the cells become and do, we grow. And we stand and run and catch footballs and dance - more or less with grace and skill. We breathe. We think!

Designer Genes


Our genes, or instructions, are coded on short segments of a long chemical chain called DNA. It is in the center of each cell of our bodies. Think of genes as information bits paired along two spiraling strands of this chemical - like snap-together beads in two long, connected strings of DNA.

Chemical Chain called DNA


Every human has the same number and set of genes, so you might think we would all be exactly the same. But the genes themselves vary a lot or a little, just as people do - and as animals do. That's why we do. For example, everyone has a pair of genes for eye color but one variation instructs the eyes to be blue while other variations order green or brown.

The complete package of genes for an animal - what makes a dog a dog - is called its genome. These packages or genomes are why people give birth to babies, dogs to puppies, and cats to kittens.

Many of the genes in other animals are similar to those in humans. After all, people and animals, like our dogs, all have to do certain things, like digesting food, so we need a similar gene for that. When we are loyal, frisky and bright-eyed - and tip over garbage cans - maybe it's those shared genes?


Next Page
Links Disclaimer and Caution
When you encounter this image link to a non-NIEHS site or the words "Non-NIEHS Link", it means that by following that link you will be leaving the NIEHS website. NIEHS is NOT responsible for non-NIEHS websites. Sites maintained by outside organizations may be changed without notice to NIEHS. Therefore, unless the link is to another U.S. government sponsored webpage, endorsement by NIEHS is not implied, and NIEHS does not guarantee their continuing safe content or privacy policies. So please ask your parent or guardian before continuing to any non-NIEHS website, and especially before providing any information via the internet or by e-mail. When last reviewed, the websites linked from the NIEHS Kids' Pages seemed suitable for you to visit, but that may have changed; if you have any difficulties or concerns with any linked materials, please let us know.